1. Technical Field
The invention relates to devices for checking a chamfer and radius of a corner surface. More particularly, the invention relates to an electronic device which provides a visual display, preferably in the form a digital readout, of certain characteristics of a chamfer and/or radius of a corner of an object on which the device is placed.
2. Background Information
It is difficult to check and measure small chamfers and small radii in making injection tooling and other machined and manufactured products. There are existing template gauges and other devices that can be placed on the chamfer and visually compared to the actual chamfer angle and length. There are also devices such as a mechanical or electronic calipers which measure across the small flat surface of the chamfer to measure its length. However, this is often difficult due to limited access for the measuring gauge when checking the radii and chamfers in holes or other locations on the object being measured.
There are also electronic digital calipers which incorporate a simple electronic sensor that reads a sensing strip placed on a moving arm of the caliper which provides the position on the strip or the distance that the strip has moved from the device. This distance is translated into an electronic digital display by a microprocessor contained in the caliper and provides a reading in metric, SAE or other format as selected by the user. However, these digital calipers are used to provide the depth of an opening or distance between two surfaces and do not provide an accurate readout as to characteristics of a chamfer, such as its length, and the length of a radius at a corner round of an object. Furthermore, many of these prior art electronic measuring devices are relatively bulky and complicated devices, two examples of which are shown in U.S. Pat. Nos. 6,766,583 and 6,205,672. Another type of mechanical chamfer gauge is shown in U.S. Pat. No. 5,714,686.
Therefore, the need exists for a relatively simple and inexpensive electronic device which can measure various characteristics of a chamfer and/or the radius of a curved surface at a corner round with the same tool, not believed possible with existing measuring devices.